An explosion breaks a rock into three parts in a horizontal plane. Two of them go off at right angles to each other. The first part of mass $1\, kg$ moves with a speed of $12 \,m s^{-1}$ and the second part of mass $2\, kg$ moves with $8 \,m s^{-1}$ speed. If the third part files off with $4 \,m s^{-1}$ speed, then its mass is ......... $kg$
$7 $
$17 $
$3$
$5$
A man of $60\,kg$ is running on the road and suddenly jumps into a stationary trolly car of mass $120\,kg$. Then. the trolly car starts moving with velocity $2\,ms ^{-1}$. The velocity of the running man was _________$ms ^{-1}$. when he jumps into the car
A mass $m$ moving horizontally (along the $x-$ axis) with velocity $v$ collides and sticks to a mass of $3m$ moving vertically upward (along the $y-$ axis) with velocity $2v$. The final velocity of the combination is
A shell is fired from a cannon with velocity $v m/sec$ at an angle $\theta $ with the horizontal direction. At the highest point in its path it explodes into two pieces of equal mass. One of the pieces retraces its path to the cannon and the speed in $m/sec $ of the other piece immediately after the explosion is
A bomb of mass $9 \,kg$ explodes into two pieces of masses $3 \,kg$ and $6 \,kg$. The velocity of mass $3 \,kg$ is $16 \,m / s$. The kinetic energy of mass $6 \,kg$ in joule is
A bullet $10\,g$ leaves the barrel of gun with a velocity of $600\,m / s$. If the barrel of gun is $50\,cm$ long and mass of gun is $3\,kg$, then value of impulse supplied to the gun will be $.....\,Ns$